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Python Python Collections (2016, retired 2019) Dictionaries Teacher Stats

Todd Bascombe
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.a{fill-rule:evenodd;}techdegree
Todd Bascombe
Full Stack JavaScript Techdegree Student 11,133 Points

need help

where did I go wrong

teachers.py
# The dictionary will look something like:
# {'Andrew Chalkley': ['jQuery Basics', 'Node.js Basics'],
#  'Kenneth Love': ['Python Basics', 'Python Collections']}
#
# Each key will be a Teacher and the value will be a list of courses.
#
# Your code goes below here.

def num_teachers(teachers = None):
    numTeachers = int(len(teachers.keys()))
    return numTeachers

def num_courses(teachers = None):
    numcourse = sum(teachers.values())

    return numcourse

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,423 Points

The argument teachers is a dictionary. The length of each dict value needs to be summed together and the total returned. The direct use of sum() might work if a list comprehension was used to create a list of the value lengths, but that's beyond this stage of the course.

:point_right: create a loop to get the length of courses for each teacher and add to a total. Return the total.

Post back if you need more help. Good luck!!